1. Field of the Invention
The present invention relates to a data processing apparatus provided with a ring-shaped data transfer path that connects a plurality of modules and an information processing method wherein the modules are processed by flexibly switching usage sequences, and relates to a computer-readable storage medium.
2. Description of the Related Art
A data processing apparatus for performing data processing by a plurality of modules connected to a ring-shaped data transfer path is discussed (Japanese Patent Application Laid-Open No. 11-167560, Japanese Patent Application Laid-Open No. 9-091262). In the ring-shaped data transfer path, a unit for temporarily storing received data is provided in each of the modules, so that the data transfer path can be divided into independent partial transfer paths, and the data can be independently transferred between the modules. With this configuration, data equivalent to a number of the modules is transferred in parallel, thereby enhancing transfer efficiency of the data.
In order to implement the data transfer between the modules, in a technology discussed Japanese Patent Application Laid-Open No. 11-167560, data to be transferred has destination information representing a module at its destination. In addition, in Japanese Patent Application Laid-Open No. 9-091262, an ID of a module is changed, without dedicated arithmetic circuits and signal lines, by providing an ID register and an ID setting flag for setting an ID for each module.
In the above-described methods, when processing of data is in progress according to a predetermined data path in a module or a ring bus, it is difficult to switch between the data paths while processing the data currently being processed. This is because, if data that is following an old data path is processed as the data is by a module in which a new data path has been set up, the processing may fail in some cases. For this reason, in the conventional method, if data along the old data path is left in a module or a ring bus when switching data paths, it is necessary to wait until predetermined processing of the left data is completed and the data is diverted from the module or the ring bus, for example. Accordingly, switching the data paths cannot be efficiently executed by the methods discussed in Japanese Patent Application Laid-Open No. 11-167560 and Japanese Patent Application Laid-Open No. 9-091262.